[T]he principles that inspired the American founding were always viewed as universal principles, which applied to all of mankind. Curiously, it wasn’t until the introduction of Historicist and Darwinian philosophy (which gave birth to Progressivism) that some Americans began to argue otherwise.

Does he mean to argue that the New History movement—inaugurated in 1912 by James Harvey Robinson’s The New History and abetted by works like Charles Beards’ An Economic Interpretation of the Constitution of the United States (1913)—gave birth to “Progressivism” fifteen years after it’d been born?

Or does he mean nothingat all—but learned from the likes of Goldberg et al.—that the best way to prevent people from criticizing the seriousness of an assertion is to pretend its “knowledge” so common as to be above reproach?

principles that inspired the American founding were always viewed as universal principles

Oh, wow. Not even close. In fact, one of the great virtues of social evolutionism was always the way in which it gave a pseudo-scientific justification to existing prejudices and, more importantly, existing practices which denied certain populations the full benefits of human or citizen rights.

There's no such thing as 'too correct' when you're trying to distinguish between yourself -- an historicist -- and an ahistoricist like Jos. Philips. I should know.

There's something very odd about that article. It opens with a reasonable question - is America only for white people? - which is elaborated upon with an e-mail from a correspondent, who feels alienated from the founding principles of the United States of America given that said principles apparently did not apply to him for much of the nation's history, what with the slavery and all. Okay, promising start. How do you resolve that?

The author just denies that there's a problem. "Actually, no! The founding principles of America were universal!" Surely any thinking person immediately wants to ask, "but what about slavery?" I mean, it's a pretty obvious counter-example, right? So obvious the author even mentions it?

I've heard people use "historicist" when they mean "relativist," which would fit the context.

Slippery language, but I understand what they mean: historical context is often a component of relativism.

What's funny about that is that in this case their the relativists, lobbying essentially for tolerance for our citizen ancestors on the grounds that they thought they were being as universalist as possible....

A few minutes' googling suggests that the root of this is Ronald Pestritto's _Woodrow Wilson and the Roots of Modern Liberalism_ (Rowman & Littlefield, 2005), which uses "historicism" in this way. The influence of "Darwininan" thinking on Wilson gets some mention, but that has probably been amplified since. The book has gotten a lot of play on right-wing blogs.

A core argument is that Wilson (and Theodore Roosevelt) marked a basic rupture in U.S. history, a betrayal of the limited-gov't design of the founders. This gets you two radically-incompatible camps: the illegitimate, elitist rulers, and the sturdy folks seeking to restore the Vision of the Founders.